Safety device for mechanically-operated rolls



A ril 2, 1929. R. w. DEMPSEY SAFETY DEVICE FOR MECHANICALLY OPERATED ROLLS Filed April 12, 1927 2 Sheets-Sheet April 1929- R.' W. DEMPSEY SAFETY DEVICE FOR MECHANICALLY OPERATED ROLLS Filed April 12, 1927 2 Sheets-Sheet Patented Apr. 2,

UNITED STATES RALPH W. DEMPSEY, 0F EIiKLAND, PENNSYLVANIA, ASSIGNOR TO JR., OF NEWTON, MASSACHUSETTS.

1,107,514 PATENT OFFICE.

EBEN H. ELLISON,

SAFETY DEVICE FOR MEGHANICALLY-OPERATED ROLLS.

Application filed. April 12,

This invention relates to safety devices for mechanically operated rolls suchas wringer rolls, calendars and thelike, and has for its principal purpose the provision of means operable on possibility of injury to the operator for positively preventing the continued operation of the rolls as a crushing instrument in case the clothing or person of the operator is in danger'of being caught or actually entering between the rolls.

object of the invention to reach this purpose is to provide power operated devices for positively separating the rolls; to provide automatic mechanism controlled by the operator in case of danger to him to transfer the effect of motive power connections normally for actuating the rolls to the work of rendering the rolls harmless as a drawing-in and crushing device; and to provide power operated mechanism having capacity for permittin bodily removal of one of a pair of rolls fi'om operative relation to the other, whereby upon an actuating impulse of the controlling or safety device one of the operated rolls may be bodily moved away from the other roll; and upon a second impulse of said safety device ,said roll may be replaced in operative relation to the other roll.

Further objects and advantages will be apparent as attributes of the construction andoperation of the apparatus now to be described in connection with a preferred species of mechanism shown in the accompanying drawings, which illustrate a recommended embodiment of theinvention applied to a wringer especially adapted for use in a tannery; for wringing soaked hides. In the drawings: I

Fig. 1 is a front elevation of a power driven wringing machine'equipped with one form of the improved safety devices;

Fig. 2 is an endelevation thereof, looking toward the left of Fig. 1;

Fig. 3 is an enlarged, somewhat diagrammatic view of a portion of the apparatus shown in Fig. 2, with the movable parts in inoperative position;

Fig. 4 is an enlarged detail of mechanism; and

Fig. 5 is an elevation opposite to that of Fig. 4, and showing a difiierent position of the movable elements thereof.

The machine may be built on any suitable strongframe 1, which for the purpose described may be constructed of stout metal the clutch 1927. Serial No. 183,206.

shapes having vertically slotted side members 6 and a work table 7 carried by a forward extension 4 of frame 1. Wringer rolls 8 and 9 are mounted between the side frames upon roller shafts 10 and 11, respectively, which are journalled at each side of the machine in two pairs of slide blocks 12 and 13 respectively, each block being movable in vertical channels 14 of the respective upright frame sides 6. In normal operative position (Figs. 1 and 2) the lower or driven roll 8 is supported in contact with upper roll 9 by sustaining means, which may be power actuated at times, for example by a pair of normally stationary eccentric cams 15, one of which is mounted on a shaft 16 under each block 12, and which bear upon and sup-port the bottom faces of the respective blocks 12 against the gravity of roll 8 and the working and other downward thrusts.

The upper roll 9 is normally held downward to operative relation with the roll 8 by gravity and any suitable adjustable tensioning means such as the heavy helical springs 17 which may be mounted between transverse plates 18 and 19 sliding in channels 14 to exert downward pressure upon the upper slide blocks 13, The degree of tension of the springs may be varied by'adjusting screws 20, actuable by handles 21. Stop ,pins 22 or other abutments may be provided in the frame channels 14 to limit downward move ment of the upper roll when the lower roll is released from contact therewith, as hereinafter described.

The lower roll shaft 10 is preferably driven bygearing comprising a member 23 on said shaft and a member 24 on a driven countershaft 25 in bearings on the frame 1 and in a frame bracket 5. Shaft 25 may be driven by a pulley 26 or otherwise; As shown in Fig. 2, the osculant sectors and common tangent to the pitch circles of the gears 23 and 24 and the channels 14 are so positioned in respect to shafts 10 and 25 as to permit said shaft 10 and gear 23 to have freedom of downward motion to release gears 23 and 24 from driving engagement and permit shaft 10 to drop with the blocks 12 when the supporting cams 15 are rotated away from normal position; for example, the counter shaft 25 is mounted so that its axisis at or above the normal hori- The shaft 16 carrying the supporting cams 15 is normally held stationary and adapted to be rotated when desired from the driveshaft 25 acting through a train of gearing comprising a gear 29 fixed to the cam shaft, an intermediate gear 30 on a stud shaft on bracket 5, a pinion 31 normally loose on a shaft 34 and meshing with gear 30, and a driven gear 33 fast on shaft 34 and meshing with the driving gear 24 on shaft. 25. A clutch mechanism at 32 is provided to lock and release shaft 34 from gear 31, and this clutch is preferably controlled by a pedal lever actuated at will by the operator, and is preferably constructed and arranged so that the normally open clutch may be closed temporarily by the pedal lever, permitting the cam shaft 16 to be rotated through 180 and then stopped. The cams 15 will thus be operated from the position of Fig. 1 to that of Fig. 3, releasing the slide blocks 12 of the lower roll shaft which will drop by gravity with the movement of the cam, causing the lower roll to separate a substantial distance from the upper roll, downward movement of which is restricted by the stop pins 22, to effect the open position of the rolls best shown in Fig. 3 of the drawings. In this position the driving connection to the rolls is broken by sepa ration of the gears 23 and 24. The clutch mechanism may also be so arranged that a second operation of the pedal lever will restore the cams to normal position, closing the rolls by rotation of shaft 16 through another half revolution.

While any suitable type of clutch and actuating devices may be utilized for this purpose, a recommended form is shown in Figs. 4 and 5 comprising in general a rotor drum 35 keyed to shaft 34, a normally stationary annular member 36 fast to pinion 31, and an intermediate clutch element carrying a restraining pin 37 which is HOIllZIlly engaged by a hook 38 of a'pivoted arm 39 held in the position of Fig. 4 to prevent any rotation of the clutch elements by friction with the surface of rotor 35. The member 36 may be an annular integral flange on the gear 31 having internal non-concentric surfaces at 43; and the inter-- mediate clutch element may comprise a disk 40 having annular segments 41 extending between thedrum 35 and the flange 36, normally in sufficient frictional contact with drum 35 to move with it when released, and having rollers 42 interposed longitudinally between the segments 41. These rollers are adapted to wedge between the rotating drum 35 and the surfaces 43 of member 36 to lock shaft 34 to pinion 31 but in the normal position of Fig. 4 in which the clutch element is locked against rotation, the rollers are released so that they do not lock together rotor 35 and pinion 31, and so that the gearing 31, 30, 29 and shaft 16 are stopped in the position of Fig. 2.

The stop pin 37 may be fixed upon the outer face of the disk 40 and the hook arm 39 is preferably pivoted at 44 to an inboard bearing bracket 45 surrounding and providing an inner bearing for the shaft 34. The hook 38 held in engagement with the pin 37 by spring 46 attached to the bracket, the elements being so disposed that a downward pressure upon the hook against the tension of the spring 46 will release the hook from the pin 37, thereby permitting the segmental clutch hub .to rotate and close the clutch.

The releasing mechanism preferably con1- prises a pivoted latch 47 and spring 51 on a rod 49 vertically movable in a hole in bracket 45, said latch normally resting over a pin 50 carried by the hook 38 (see Fig. 4). The rod 49 is connectedby lever 53 and link 54 toa pedal lever 55 pivoted to the frame base at 56 and normally held in inoperative position by a coil spring 57 tending to lift the pedal. The rod 49 is thus supported in the elevated position of Fig. 4, with pawl close to, but not bearing downwardly upon, the hook pin 50.

Depression of the pedal 58 by the operator of the machine carries the actuating rod 49 downwardly until its movement is stopped by contact of a fixed collar 59 against the bracket 45. The latch 47, acting upon pin 50, swings the hook arm 39 downwardly to release pin 37 allowing pinion 31 to be clutched to shaft 34 as aforesaid, so that gear 29 and shaft 16 are driven by the driving gear 24 through the intermediate gear train, and the eccentric cams 15 are rotated, permitting the lower roll to drop bodily away from the upper roll.

-After latch 47 passes by the hook pin 50 the hook arm is returned to normal position by spring 46, and the hook will again engage the clutch pin 37 when the clutch element has rotated through one revolution,

thereby stopping the cam shaft 16 and its attachments at or about one half revolution, the gear 29 having twice as many teeth as gear 30. Shaft 16 and its attachmentshave not suflicient momentum to turn the eccentrics 15 against the. weight of the roll 8. The eccentric cams 15 will thus rotate through 180 degrees and stop in the position of Fig. 3. On a second depression of the pedal another half revolution of shaft 16 will occur, to restore the lower roll to normal working position.

The described devices provide a safety dcv1ce for power driven rolls which .will act lnstantly on the practically instinctive operation of pedal 58 without shutting off the mo tive power of the machine, and without having to wait for the momentum of driven parts of the machine to be overcome, to se arate the rolls from crushing relation beyon possibility that the hand or clothing of the operator will be taken in between the rolls. The space provided by the separation of the rolls will depend upon the eccentricity of the cams 15, which may be any desired quantity, but it is recommended that this be sufficient to let the arm of the operator pass between the rolls without seizure.

After the operator has separated the rolls, the work in them is released, and the rolls may be started again without delay, and without failure to perform the work in the material in the rolls at the time when the.

danger intervened.

I claim:

1. Safety device for power driven, rolls having therein in combination, rolls in coacting relation and means sustaining one of said rolls for rotation in said relation in combination with power actuated devices adapted to whereby the operator may cause said power actuated means to become operative.

3. Safety device for power 'driven rolls comprising in combination a power actuated connection for .at least one of said rolls, sus taining means for one of said rolls, a connectionfor displacing said sustaining means, and means for coupling said dis lacing connection to said power actuate connection adapted to be operated on the occurrence of danger to the operator.

4. In combination with a machine having normally coacting rolls, means for driving the rolls, a movable support for one of the rolls, and means under the control of the operator and operable by said drivin means for moving said support, whereby t e rolls are separated from each other.

5. In combination with a machine having normally coa-ctin rolls, means for driving the rolls, a mova le support for one of the rolls, a normally open clutch, and means operated by the driving'means upon shifting said clutch for moving said sup ort, whereby the said supported roll is moved bodily away from the other roll.

6. In combination with a machine having normally coacting upper and lower rolls, means for driving the rolls, a movable support beneath the lower roll, a normally open clutch, means actuated by the operator of the machine for closing the clutch, and means operated by the driving means upon the closing of the clutch for moving said support downwardly, whereby the lower roll is separated from the upper roll.

7. In combination with a machine having normally coacting upper and lower rolls, means for driving the lower roll, a normally stationary eccentric support beneath the lower roll, a normally open clutch, means a driving gear meshed with said driven gear,

a cam shaft beneath the lower roll, normally stationary eccentrics on the cam shaft for supporting the lower roll against the upper roll, a gear on the cam shaft, means connecting the driving gear to the cam shaft gear including a normally open clutch, and means for closing the clutch to drive the cam shaft gear,'whereby the eccentric supports are rotated downwardly and the lower roll is separated from the upper roll.

9. Safety device for power driven rolls having therein in combination, rolls in coacting relation and means adapted in one position to sustain one of said rolls for rotation in said relation in combination with mechanism including a clutch for displacin said sustaining means and causing the rdlls to separate, and means. in reach ofthe operator erative relation between the pair of rolls,

means having an element continuously power actuated for moving said sustaining means to separate the rolls, a clutch for connecting said continuouslyactuated element to' means adapted to displace said sustaining means, and means whereby the operator may shift said clutch. 1 Y

11. Safety device for power driven rolls comprising in combination a power actuated connection for at least one of said rolls, sustaining means for one of said rolls, a connection for displacing and for returning to operative position said sustaining means, and means for coupling said displacing connection to said power actuated connection adapted to be operated onthe occurrence of danger to the operator comprising a clutch and operator-actuated controlling means therefor adapted to restrict the operation of said displacing and returning means to displacing or to returning said sustaining means.

12. In a machine having power-actuated squeezing rolls, means for tensioning one roll against the other comprising movable bearing blocks, adjustable spring means therefor, and a limit stop for said bearing blocks, in combination with hearing blocks for the other roll, means permitting said roll and bearing blocks freedom of motion away from the limit of motion of the tensioned roll, means normally restraining such motion, and a connection for operation by the operator of the machine for withdrawing said restraining means.

13. In a safety device for machines having power actuated rolls including a roll having a tensioning device tending to force it against another roll, power-operated devices for bodily moving said other roll toward and away from its operative position including a clutch, and manually-operable controlling connections therefor, one operation of the clutch causing removal of said roll from its working position and another operation of said clutch causing said roll to be returned to its operating position.

Signed by me at E'lkland, Pennsylvania, this sixth day of April, 1927.

RALPH W. DEMPSEY. 

